The Michigan DNR reservation website has a notice for the Rifle River Recreation Area that they will be doing some road construction late this summer and early autumn.
Grousehaven (modern) Campground will be closed from September 8-October 15
Devoe, Ranch, Spruce, and Org (rustic) Campgrounds will be closed from August 16-September 3 and September 30-October 15.
Cabin users will be entering the park through the south entrance gate from September 30-October 15
I am not sure exactly what they will be doing to the road but I know the dirt road heading back to the southern end of the park was getting really rough. It is great that they are making improvements to the roads.